kernel: remove outdated hack

Since mtwifi was removed, this can go too.

Signed-off-by: Tianling Shen <cnsztl@immortalwrt.org>

target/linux/generic/hack-5.10/998-add-ndo-do-ioctl.patch

@@ -1,12 +0,0 @@
---- a/net/wireless/wext-core.c
-+++ b/net/wireless/wext-core.c
-@@ -956,6 +956,9 @@ static int wireless_process_ioctl(struct
- 		else if (private)
- 			return private(dev, iwr, cmd, info, handler);
- 	}
-+	/* Old driver API : call driver ioctl handler */
-+	if (dev->netdev_ops->ndo_do_ioctl)
-+		return dev->netdev_ops->ndo_do_ioctl(dev, (struct ifreq *) iwr, cmd);
- 	return -EOPNOTSUPP;
- }
-